Neural adaptations after 4 years vs 12 weeks of resistance training vs untrained

The purpose of this study was to compare the effect of resistance training (RT) duration, including years of exposure, on agonist and antagonist neuromuscular activation throughout the knee extension voluntary torque range. Fifty‐seven healthy men (untrained [UNT] n = 29, short‐term RT [12WK] n = 14, and long‐term RT [4YR] n = 14) performed maximum and sub‐maximum (20%‐80% maximum voluntary torque [MVT]) unilateral isometric knee extension contractions with torque, agonist and antagonist surface EMG recorded. Agonist EMG, including at MVT, was corrected for the confounding effects of adiposity (ie, muscle‐electrode distance; measured with ultrasonography). Quadriceps maximum anatomical cross‐sectional area (QACSA_MAX; via MRI) was also assessed. MVT was distinct for all three groups (4YR +60/+39% vs UNT/12WK; 12WK +15% vs UNT; 0.001 < P ≤ 0.021), and QACSA_MAX was greater for 4YR (+50/+42% vs UNT/12WK; [both] P < 0.001). Agonist EMG at MVT was +44/+33% greater for 4YR /12WK ([both] P < 0.001) vs. UNT, but did not differ between RT groups. The torque‐agonist EMG relationship of 4YR displayed a right/down shift with lower agonist EMG at the highest common torque (196 Nm) compared to 12WK and UNT (0.005 ≤ P ≤ 0.013; Effect size [ES] 0.90 ≤ ES ≤ 1.28). The torque‐antagonist EMG relationship displayed a lower slope with increasing RT duration (4YR < 12WK < UNT; 0.001 < P ≤ 0.094; 0.56 ≤ ES ≤ 1.31), and antagonist EMG at the highest common torque was also lower for 4YR than UNT (?69%; P < 0.001; ES = 1.18). In conclusion, 4YR and 12WK had similar agonist activation at MVT and this adaptation may be maximized during early months of RT. In contrast, inter‐muscular coordination, specifically antagonist coactivation was progressively lower, and likely continues to adapt, with prolonged RT.     

Electromyographic activity of masticatory, neck and trunk muscles of subjects with different skeletal facial morphology--a cross-sectional evaluation

The electromyographic pattern activity of masticatory, neck and trunk muscles was assessed using surface electromyography (sEMG) in 60 Caucasian adult females (20 subjects in skeletal class I, 20 subjects in skeletal class II and 20 subjects in skeletal class III), classified on the base of their skeletal class (ANB angle), corrected on the base of maxillary and mandibular rotations. The sEMG activity was recorded at mandibular rest position and during maximal voluntary clenching. At mandibular rest position, the sEMG activities of masseter and anterior temporal muscles were significantly higher in class III subjects than in class I and class II subjects, that showed no significant difference between them. Then, the sEMG activities of posterior cervicals and upper trapezius were significantly higher in skeletal class III subjects than in the other two groups. During maximal voluntary clenching, no significant difference was observed in the sEMG activity of masticatory muscles among the three considered groups. However, the sEMG activities of posterior cervicals and upper trapezius were significantly higher in skeletal class III subjects than in the other two groups, which showed no significant difference between them. In conclusion, the skeletal class seems to affect the sEMG pattern activity of masticatory, neck and trunk muscles.     

Review of clinical EMG studies related to muscle and occlusal factors in healthy and TMD subjects

Several electronic instruments have been developed as adjuncts to objectively record the dysfunctional features of temporomandibular disorders and to study the effectiveness of various treatment interventions. The aim of this review was to assess the value and contribution of clinical electromyographic research in the understanding of asymptomatic and dysfunctional muscle function and the therapeutic effects of interocclusal appliances. For this purpose MedLine and PubMed searches were conducted with the following main keywords alone and in various combinations: electromyography, muscles of mastication, masseter, temporalis, temporomandibular, TMD, utility, validity, repeatability, rest, postural, vertical dimension, occlusal, splint, treatment. The review includes critical evaluation, discussion and conclusions regarding electromyographic studies in asymptomatic and dysfunctional muscles, rest position, occlusal parameters and interocclusal appliances, as well as a critical summary and proposals for further research. Much of earlier critique of many electromyographic studies still applies regarding comparative sample selections, research designs, analyses and conclusions. The areas not well-understood include normal biological variation, capacity for adaptation, fluctuations regarding the clinical course and multidimensional features of temporomandibular disorders and long-term follow-up data, especially in studies that evaluate the effectiveness of therapeutic measures. Considering the required improvements in technical and research designs features and critical appraisal electromyographic research could have value as an adjunct research tool to study features of craniofacial muscle-related dysfunction. Until electromyographic measures are correlated with other multidimensional, especially subjective and pain-related methods, the clinical use of this method for diagnostic purposes of temporomandibular disorders remains in doubt, and is not at present recommended.     

干扰型分析在诊断神经肌肉疾病中的应用

应用ＳｔａｌｌｂｅｒｇＥ的干扰型分析技术，对１０例正常人和２０例神经肌肉疾病患者进行传统肌电图和干扰型分析检测。结果表明该分析技术较之常规的运动单位定量分析具有快捷，准确率高的优点。     

甲钴胺与马来酸桂哌齐特联合治疗糖尿病下肢神经病变的疗效观察

目的：探讨甲钴胺与马来酸桂哌齐特在2型糖尿病合并下肢周围神经病变治疗中的疗效及血管内皮功能的变化.方法：选择2型糖尿病合并下肢周围神经病变的病例60例,随机分甲钴胺治疗组（1组）和甲钴胺与马来酸桂哌齐特治疗组（2组）,每组30例,1组给予甲钴胺治疗,2组在甲钴胺治疗的基础上加用马来酸桂哌齐特治疗,疗程14天,治疗前后观察临床症状,测定血管内皮细胞功能和肌电图.结果：经过治疗,1组运动传导速度、感觉传导速度,以及临床症状有一定程度的改善,但差异无显著性意义（P＞0.05）,2组治疗后运动传导速度、感觉传导速度明显增快,同时临床症状改善明显（P＜0.01）;两组治疗前血内皮素、D-二聚体和C反应蛋白（CRP）均高于正常,治疗前后比较差异有显著性意义（P＜0.05）,而1组血内皮素、D-二聚体和CRP均有一定程度的下降但差异无显著性意义（P＞0.05）.结论：甲钴胺与马来酸桂哌齐特联合治疗在2型糖尿病合并下肢周围神经病变治疗中可改善血管内皮的功能和下肢周围神经病变,缓解临床症状,疗效显著.     

姿态与肌电融合的脑卒中患者上肢运动功能实时评估方法

摘要 目的：提出了一种基于运动姿态与肌电融合的脑卒中患者上肢运动功能实时评估方法。 方法：选取一定数量处于不同Brunnstrom分期的脑卒中患者。首先运用姿态与肌电检测传感器,分别采集康复动作评估过程中不同分期患者上肢运动姿态与表面肌电数据;其次分别提取患肢运动姿态与表面肌电数据特征,在融合姿态与肌电特征信息基础上获取患者上肢运动功能评估数据集;最后,选取具有较好实时分类性能的模糊支持向量机作为分类器,运用评估数据集测试上肢运动功能评估效果。 结果：基于模糊支持向量机构建的运动功能分类器经过离线训练后,姿态与肌电融合的分类器对脑卒中患者上肢运动功能实时评估准确率平均达到83%,且较单纯基于运动姿态(75%)或肌电(74%),具有更好的评估效果。 结论：姿态与肌电融合的上肢运动功能实时评估方法,能较准确地对脑卒中患者上肢运动功能进行实时Brunstrom分期。     

PNF技术对脑卒中患者躯干控制的疗效观察及躯干屈伸肌群表面肌电指标分析

目的：观察本体感觉神经肌肉促进技术（PNF）对脑卒中患者躯干控制的疗效及躯干屈伸肌群表面肌电信号的变化。方法：将30例脑卒中偏瘫患者随机分为观察组和对照组各15例,对照组给予常规康复干预,观察组在此基础上给予PNF躯干模式训练。在治疗前及治疗4周后,采用躯干控制能力测试(TCT)、Berg平衡功能量表(BBS)、Fugl-Meyer运动功能量表(FMA)以及表面肌电均方根值(RMS)对患者进行评定。结果：治疗4周后,2组患者TCT、BBS及FMA评分较治疗前均明显提高（均P＜0.05）,且观察组各项评分较对照组均明显提高（均P＜0.05）。治疗前,2组患者患侧腹直肌及竖脊肌RMS组内比较均小于健侧（均P＜0.05）;治疗4周后,2组患者患侧腹直肌及竖脊肌RMS较治疗前均明显提高（均P＜0.05）,且观察组健侧腹直肌及竖脊肌RMS较治疗前均明显提高（均P＜0.05）;观察组患者健患侧腹直肌及竖脊肌RMS较对照组均明显提高（均P＜0.05）。结论：PNF躯干训练技术可以明显增强脑卒中偏瘫患者躯干肌群力量,提高躯干控制能力,改善平衡功能,从而促进患者运动功能恢复。     

延髓型重症肌无力喉肌电指标变化的临床价值

目的探讨延髓型重症肌无力患者电视胸腔镜下胸腺扩大切除术（video-assisted thoracoscopic extended thymectomy,VATET）后喉肌电指标测定的临床价值。方法回顾分析2002年6月～2011年7月我科36例延髓型重症肌无力（延髓型组）行VATET的临床资料,对术前后喉肌电指标进行分析,选取同期36例健康受试者作为对照组。结果延髓型组术前喉内肌肌电振幅（210．68±75．42）μV,较对照组（309．40±55．33）μV明显缩窄（t=6．332,P=0．000）;时程（7．68±0．57）ms较对照（5．42±0．34）mB明显延长（t=-20．431,P=0．000）;募集相最大电位（1132．18±467．19）μV较对照组（1675．00±532．85）μV明显缩窄（t=4．596,P=0．000）,术后2组比较仅时程有明显差异（t=6．375,P=0．000）。延髓型组喉内肌群术后肌电振幅（312．91±69．43）μV,较术前（210．68±75．42）μV明显变宽（t=-5．983,P=0．000）;术后时程（6．19±0．64）m8较术前（7．68±0．57）m8明显缩短（t=10．431,P=0．000）;术后募集相最大电位（1557．67±521．45）斗V较术前（1132．18±467．1）μV明显变宽（t=-3．646,P=0．000）;喉外肌仅肌电振幅差异显著[（139．36±74．26）μV vs．（102．75±63．22）μV,t=-2．252,P=0．027]。术后喉肌电图正常的患者疗效有效率89．3％（25／28）,喉肌电图异常的患者疗效有效率37．5％（3／8）,2组比较有统计学差异（χ2=6．891,P=0．009）。结论延髓型重症肌无力患者肌电指标异常,VATET可有效改善各项指标,缓解相关的临床症状。